Modelling tasks in terms of task work without using resources

You can model tasks in terms of task work without having to assign resources to them. This enables you to calculate the duration of tasks directly from the task work and the work rate that are recorded against them, and to have the task work amount or the work rate updated automatically when the duration of a task is changed.

Modelling tasks in terms of task work enables you to answer questions such as:

  • I know how many bricks are needed to build this wall and I know how many bricks can be laid in a single day. How long will it take to build the wall?
  • Bricklayer A is capable of laying 50 more bricks per day than bricklayer B. How much sooner would bricklayer A complete the task than bricklayer B?
  • I have discovered that 1,200 bricks will be needed to build this wall, rather than 800. How much longer will the wall take to build?
  • I need to complete this wall two days ahead of schedule. How many bricks per day will my bricklayers need to lay in order to achieve this?

Recording task work and work rate against tasks

In order to model a task in terms of task work, you must record both the task work amount and a work rate against the task. To do this:

  1. Right-click the task and select Properties. The Bar and Task Properties dialog appears.
  2. Click the Task tab, then click Effort & Modelling in the left pane of the dialog.
  3. Enter the amount of work that needs to be carried out to complete the task in the Task work field. For example, if 800 bricks need to be laid to complete the tasks, enter 800.
  4. Select the unit in which to measure the task work in the Work unit field. For example, task work may be measured in units such as bricks, tonnes or metres.
  5. Record the work rate in the Task work rate and Time unit fields. For example, if 100 bricks can be laid per day, enter 100 in the Task work rate field and select Day in the Time unit field.

You can also record this information against tasks using the properties view, or by displaying the appropriate 'task work' fields in the spreadsheet.

Select 'None' in the Work unit and Time unit fields to indicate that there is absolutely no task work on a task - and that there never has been and never will be task work. This is useful when analysing task work remaining because without being able to set the work unit to 'None', there is no difference in the spreadsheet between a task that has never had task work and one that Is 100% complete (the remaining task work would then be zero too).

Modelling tasks in terms of task work

Once you have recorded the amount of task work and a work rate against a task, you can model the task in terms of task work as follows:

  • If you change the task work amount, the duration of the task is updated automatically according to the specified work rate. For example, a task with a task work amount of 800 bricks and a work rate of 100 bricks per day would have a duration of 8d. If you changed the task work amount to 600 bricks, the task duration would be updated automatically to 6d.
  • If you change the task work rate of a task against which task work has been recorded, the duration of the task is updated accordingly to reflect the revised work rate. For example, if a 10d task has 100 units of task work with a work rate of 10 units per day and you change the work rate to 20 units per day, the task duration will change to 5d.

    Changing the task work rate of a task can result in fractional task durations. For example, if you changed the work rate of the task in the above example to 8 units per day, the task duration would change to 12d 4h. If you like to work in whole time units - for example, in whole days rather than in part days - this behaviour is undesirable.

    You can configure Powerproject to adjust the task work rate downwards automatically if necessary when it is changed to produce a non-fractional task duration - one with a whole number of time units. If you do this, changing the work rate of the task in the above example to 8 units per day would result in the task work rate being adjusted automatically to 7.69 units per day and a task duration of 13d. The task work rate is adjusted so that the task duration has a whole number of the time unit specified in the task work rate. For example, if a 10d task had 100 units of task work with a work rate of 50 units per week and you changed the work rate to 40 units per week, the task work rate would be adjusted automatically to 33.33 units per week and the task duration would change from 10d to to 15d - ie from 2w to 3w - as 'week' is the time unit specified in the task work rate.
  • You can specify whether the task work amount or the work rate should be updated if you change the duration of a task.
    If you specify that the task work amount should be updated and you change the duration, the task work amount is updated automatically according to the specified work rate. For example, a task with a task work amount of 600 tiles and a work rate of 50 tiles per day would have a duration of 12d. If you changed the duration to 10d, the task work amount would be updated automatically to 500 tiles.

    If you specify that the work rate should be updated and you change the duration, the work rate is updated automatically according to the specified task work amount. For example, a task with a task work amount of 200 blocks and a work rate of 50 blocks per day would have a duration of 4d. If you changed the duration to 5d, the work rate would be updated automatically to 40 blocks per day.

Marking progress on tasks by recording the amount of task work that has been performed

You can mark progress on tasks that are modelled in terms of task work by editing the actual task work, the remaining task work, or the overall percent complete. You can record this information in a number of ways, including by entering progress information into the appropriate fields in the spreadsheet. A simple way to mark progress on such tasks is by using the Enter Progress dialog. To do this:

  1. Select the task against which you want to mark progress.
  2. On the Home tab, in the Progress group, click Enter Progress and select Enter Progress from the menu that appears. The Enter Progress dialog appears.
  3. On the Task tab, either record the amount of task work that has been completed in the Task work row, or record the overall percentage progress in the Overall percent row.

If you have partially progressed a task that is modelled in terms of task work and you alter the task work amount, work rate or duration of the task, the completed section of the task is unaffected by the change; only the uncompleted section of the task is remodelled.

Sorting/grouping and filtering on task work

You can sort/group tasks according to the 'task work' fields.

You can filter for tasks with task work of one or more particular work units, and for tasks with particular amounts of task work.

Related Topics:

Task work fields

Using histograms to graph activity days and task work